JP2005130670A - Motor drive and electric vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a motor drive reduced in size, and an electric vehicle mounting it. <P>SOLUTION: The motor drive comprises a motor generating a torque and a regenerative power through regenerative braking, a power converter supplying the motor with power being converted into torque, a smoothing capacitor connected between the positive and negative electrodes of the power converter, a DC power supply connected between the positive and negative electrodes of the power converter, and a regenerative power blocking means connected between the DC power supply and the smoothing capacitor wherein the regenerative power blocking means blocks regenerative power supply to the DC power supply when the motor performs regenerative braking. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a motor drive device and an electric vehicle, and more particularly to a motor drive device having a motor that generates regenerative power by regenerative braking and an electric vehicle equipped with the motor drive device.

There is a strong demand for motors used for running electric vehicles to cover a wide speed range (rotational speed range). However, generally, the torque of the motor is limited to a maximum value as shown in FIG. On the other hand, for example, in Patent Document 1 or the like, in order to boost the DC voltage of the power converter (inverter), a booster circuit including a reactor is provided, a voltage higher than the power supply voltage is supplied to the inverter, and torque is increased. The maximum limit is increased.
JP 2003-1553577 A

  A motor used for driving an electric vehicle is strongly demanded to be downsized with a wide speed range. However, in Patent Document 1, since a booster circuit including a reactor and the like is provided, a driving device is large. It will become.

  A first feature of the present invention is connected between a motor that generates regenerative power by rotational force and regenerative braking, a power converter that supplies power converted to rotational force to the motor, and a positive and negative electrode of the power converter. A motor drive device having a smoothing capacitor, a DC power source connected between the positive and negative electrodes of the power converter, and a regenerative power blocking unit connected between the DC power source and the smoothing capacitor, The gist is to prevent regenerative power from being supplied to a DC power source when the motor performs regenerative braking.

  The second feature of the present invention is that a plurality of motors that generate regenerative power by rotational force and regenerative braking, a plurality of power converters that respectively supply power converted to rotational force to the motor, and at least some power A smoothing capacitor connected between the positive and negative electrodes of the converter, a DC power source connected between at least some of the power converters, and a regenerative power blocking means connected between the DC power source and the smoothing capacitor. The regenerative power blocking means has a gist of blocking regenerative power from being supplied to a DC power source when the motor performs regenerative braking.

  According to a third aspect of the present invention, there is provided a travel motor that generates regenerative power by driving force and regenerative braking of an electric vehicle, a power converter that supplies power converted into driving force to the motor, An electric vehicle having a smoothing capacitor connected between the negative electrodes, a DC power source connected between the positive and negative electrodes of the power converter, and a regenerative power blocking means connected between the DC power source and the smoothing capacitor. The gist of the power blocking means is to block regenerative power from being supplied to the DC power source when the traveling motor performs regenerative braking.

  A fourth feature of the present invention is that a plurality of motors that generate regenerative power by rotational force and regenerative braking, a plurality of power converters that respectively supply power converted to rotational force to the motor, and at least some power A smoothing capacitor connected between the positive and negative electrodes of the converter, a DC power source connected between at least some of the power converters, and a regenerative power blocking means connected between the DC power source and the smoothing capacitor. The regenerative power blocking means prevents the regenerative power from being supplied to the DC power source when the motor performs regenerative braking, and at least some of the motors use the rotational force as the driving force of the electric vehicle. The gist is that it is a motor for traveling.

  ADVANTAGE OF THE INVENTION According to this invention, the motor drive device reduced in size and the electric vehicle carrying the motor drive device can be provided.

  Embodiments of the present invention will be described below with reference to the drawings. In the description of the drawings, the same or similar parts are denoted by the same or similar reference numerals.

(First embodiment)
As shown in FIG. 1, the motor driving apparatus according to the first embodiment of the present invention supplies a motor 1 that generates regenerative power by rotational force and regenerative braking, and power that is converted to rotational force to the motor 1. Power converter (for example, inverter) 2, smoothing capacitor 3 connected between the positive and negative electrodes of inverter 2, DC power supply 4 connected between the positive and negative electrodes of inverter 2, DC power supply 4 and smoothing capacitor 3 And regenerative power blocking means 15a connected between them. In the motor drive device shown in FIG. 1, the regeneration prevention means 15a includes a diode 5 and a semiconductor switch 6 connected in parallel. The forward direction of the diode 5 is directed from the positive electrode of the DC power supply 4 to the inverter 2.

  The motor 1 is a three-phase AC synchronous motor, and the three terminals of the motor 1 are connected to the output terminal of the inverter 2. A smoothing capacitor 3 for suppressing voltage fluctuation is connected between the DC positive and negative terminals of the inverter 2.

  The motor drive device further includes a voltage sensor 7 that measures the voltage value Vc of the smoothing capacitor 3, a motor torque controller 8, a motor current controller 9, and a current that measures the current flowing between the motor 1 and the inverter 2. Sensors 10 a and 10 b, a rotational position sensor 11, a phase / speed calculator 12, and an inverter voltage controller 13 are included.

  Current sensor 10 a detects U-phase current iu of motor 1, and current sensor 10 b detects W-phase current iw of motor 1. The rotational position sensor 11 is an encoder, a resolver, or the like that detects the rotor position of the motor 1. The phase / speed calculator 12 calculates an electrical phase θ representing the rotor position, and calculates the electrical angular velocity coordinate ω of the motor 1 from the time derivative of the phase θ. The motor torque controller 8 receives the motor torque command T * and outputs motor dq axis current command values id * and iq * that realize the motor torque command T *. Specifically, the motor torque controller 8 refers to a prepared map from the electrical angular velocity coordinate (motor velocity) ω, the voltage Vc of the smoothing capacitor 3 and the motor torque command value T *, and the motor dq axis current. Command values id * and iq * are obtained. The motor current controller 9 generates an inverter drive signal DI for turning on / off the switch of the inverter 2 in order to realize the motor dq axis current command values id * and iq * output from the motor torque controller 8. The inverter voltage controller 13 controls the voltage Vc of the smoothing capacitor 3 by turning on / off the semiconductor switch 6. Specifically, the inverter voltage controller 13 generates a switch drive signal DSW for turning on / off the semiconductor switch 6 using a hysteresis comparator based on the voltage command value Vc * and the voltage Vc.

  As shown in FIG. 2, the motor current controller 9 of FIG. 1 includes subtracters 100a and 100b, a three-phase / dq coordinate converter 101, a dq current controller 102, a non-interference controller 103, and an adder. 104 a, 104 b, dq / 3 phase coordinate converter 105, and PWM generator 106.

  The three-phase / dq coordinate converter 101 performs coordinate conversion from the three-phase alternating current of the motor 1 to the dq-axis current. Specifically, the U-phase current iu and the W-phase current iw of the motor 1 are converted into a d-axis current id and a q-axis current iq using the electrical phase θ representing the rotor position. The dq coordinate is a coordinate system that rotates in synchronization with the fundamental wave component of the magnetic flux of the motor 1.

  The subtractor 100a obtains a current control deviation between the motor dq axis current command value id * and the d axis current id. The subtractor 100b obtains a current control deviation between the motor dq axis current command value iq * and the q axis current iq.

  The dq current controller 102 performs d-axis current control and q-axis current control so that the current control deviation becomes zero, and outputs control signals vd and vq.

  The non-interference controller 103 is a feedforward compensation unit for the speed electromotive force of the motor 1.

  The adders 104a and 104b calculate the d-axis control voltage vd * and the q-axis control voltage vq * by adding the output signals vd_cmp and vq_cmp from the non-interference controller 103 to the control signals vd and vq.

  The dq / 3-phase coordinate converter 105 performs coordinate conversion from the dq-axis current to the three-phase AC of the motor 1. Specifically, the d-axis current vd * and the q-axis current vq * are converted into the three-phase currents vu *, vv *, and vw * of the motor 1 using the electrical phase θ representing the rotor position.

  The PWM generator 106 receives the three-phase currents vu *, vv *, vw * and the voltage Vc of the smoothing capacitor 3 and outputs an inverter drive signal DI. Specifically, PWM generation is performed by comparing the triangular wave having the voltage Vc at the peak value with the three-phase currents vu *, vv *, and vw *.

  The inverter drive signal DI causes the switches of the inverter 2 shown in FIG. 1 to perform on / off operations, so that a voltage is applied to the terminal of the motor 1 and a current flows. As a result, motor torque is generated and the motor 1 is driven.

  The principle of boosting by preventing regeneration will be described. When the motor 1 is regeneratively operated to obtain a braking force, the motor 1 generates regenerative power, and current flows from the motor 1 through the inverter 2 toward the battery (DC power supply) 4 and the smoothing capacitor 3. Here, when the semiconductor switch 6 is turned on, most of the regenerative power is charged in the battery 4, and the voltages of the battery 4 and the smoothing capacitor 3 become substantially equal. When the switch 6 is off, no current flows to the battery 4, so regenerative power does not charge the battery 4 but charges the smoothing capacitor 3. As a result, the voltage of the smoothing capacitor 3 becomes higher than the voltage of the battery 4. In this way, the regeneration prevention means 15a boosts the voltage of the smoothing capacitor 3 by preventing the regenerative power from being supplied to the DC power source (battery) 4 when the motor 1 performs regenerative braking.

  The operation of the inverter voltage controller 13 will be described with reference to FIG.

  (A) First, in step S1, a switch drive signal DSW for turning on the semiconductor switch 6 is output as an initial state.

  (B) Next, in step S2, a value obtained by subtracting the hysteresis band ΔVc from the voltage command value Vc * is compared with the voltage Vc of the smoothing capacitor 3 using a hysteresis comparator. If the voltage Vc of the smoothing capacitor 3 is small as a result of the comparison (YES in step S2), the process proceeds to step S3, and a switch drive signal DSW for turning off the semiconductor switch 6 is output. On the other hand, if the voltage Vc of the smoothing capacitor 3 is large (NO in step S2), the process returns to immediately before this comparison calculation. That is, the inverter voltage controller 13 monitors whether or not the voltage Vc of the smoothing capacitor 3 is smaller than (Vc * −ΔVc) in the step S2.

  (C) In step S3, by turning off the semiconductor switch 6, the voltage Vc of the smoothing capacitor 3 is charged by the regenerative power and rises.

  (D) In step S4, the hysteresis comparator is used to compare the value obtained by adding the hysteresis band ΔVc to the voltage command value Vc * and the voltage Vc of the smoothing capacitor 3. If the voltage Vc of the smoothing capacitor 3 is large as a result of the comparison (YES in step S4), the process returns to step S1 to output the switch drive signal DSW for turning on the semiconductor switch 6. If the voltage Vc of the smoothing capacitor 3 is small (NO in step S4), the process returns to immediately before the comparison calculation. That is, the inverter voltage controller 13 monitors whether or not the voltage Vc of the smoothing capacitor 3 becomes higher than (Vc * + ΔVc) in step S4.

  (E) When the semiconductor switch 6 is turned on in the S1 stage, the charge stored in the smoothing capacitor 3 is discharged so as to charge the battery 4, and the voltage Vc of the smoothing capacitor 3 decreases. The above loop is repeated.

  Thus, the motor drive device according to the first embodiment can control the voltage Vc of the smoothing capacitor 3 to be higher than the voltage of the battery 4 using the regenerative power of the motor 1. For this reason, when the operation of accelerating again after the motor 1 is decelerated, the voltage limit is temporarily increased at the time of reacceleration, and high responsiveness can be exhibited.

  By mounting the motor drive device according to the first embodiment as a traveling motor for an electric vehicle, the regenerative brake is operated to decelerate before the entrance of the curve, and the voltage Vc of the smoothing capacitor 3 is set to the voltage of the battery 4. Control higher than. In order to pass the curve with the accelerator off and accelerate near the curve exit, the upper limit of torque when the motor 1 is powered is limited by the voltage of the battery 4 as shown in FIG. Instead, the second voltage limit is determined by the voltage Vc of the smoothing capacitor 3 that is higher than the voltage of the battery 4. For this reason, the acceleration after passing a curve becomes high, and a comfortable maneuverability can be provided to the driver.

  According to the first embodiment, the voltage Vc of the smoothing capacitor 3 can be boosted by preventing regeneration of the regenerative power of the motor 1 to the battery 4, so that the voltage is boosted using a device such as a DCDC converter. Compared with the case, the whole apparatus can be reduced in size. As a result, when powering again after regenerative braking, the acceleration of the motor 1 is improved because a high voltage can be used.

  Further, by forming the regenerative power blocking means 15a by the semiconductor switch 6 and the diode 5 connected in parallel, the regenerative power to the battery 4 is adjusted by the on / off operation of the semiconductor switch 6, and the voltage Vc of the smoothing capacitor 3 is adjusted. Therefore, the upper limit of the voltage of the inverter 2 or the smoothing capacitor 3 is not exceeded.

(Modification of the first embodiment)
As shown in FIG. 5, in the motor drive device according to the modification of the first embodiment, the regenerative power blocking means 15b is the relay 6a and the relay 6a is compared with the motor drive device shown in FIG. The difference is that it is connected between the DC power supply 4 and the smoothing capacitor 3. Other configurations are the same, and a description thereof will be omitted.

  The inverter voltage controller 13 controls the voltage Vc of the smoothing capacitor 3 by turning on / off the relay 6a. Specifically, the inverter voltage controller 13 generates a switch drive signal DSW for turning on / off the relay 6a using a hysteresis comparator based on the voltage command value Vc * and the voltage Vc.

(Second Embodiment)
As shown in FIG. 6, the motor driving apparatus according to the second embodiment includes two motors (first and second motors 1a and 1b) and power to the first and second motors 1a and 1b. Two power converters (first and second inverters 2a and 2b) to be supplied respectively, a smoothing capacitor 3 connected between the positive and negative electrodes of the first and second inverters 2a and 2b, and the first and second DC power source (battery) 4 connected between the positive and negative electrodes of the inverters 2a and 2b, and regenerative power blocking means 15a connected between the battery 4 and the smoothing capacitor 3. That is, in the second embodiment, there are two combinations of the inverters 2a and 2b and the motors 1a and 1b. The positive and negative buses of the respective inverters 2 a and 2 b are connected in parallel to the smoothing capacitor 3, and a circuit 15 a in which a diode 5 and a semiconductor switch 6 are connected in parallel is formed between the smoothing capacitor 3 and the battery 4. .

  The motor drive device further includes a voltage sensor 7 that measures the voltage value Vc of the smoothing capacitor 3, motor torque controllers 8a and 8b, motor current controllers 9a and 9b, motors 1a and 1b, and inverters 2a and 2b. Current sensors 10a to 10d for measuring a current flowing therebetween, rotational position sensors 11a and 11b, phase / speed calculators 12a and 12b, an inverter voltage controller 13 and a vehicle controller 14 are included. That is, corresponding to the combination of the first and second inverters 2a and 2b and the first and second motors 1a and 1b, the motor torque controllers 8a and 8b, the motor current controllers 9a and 9b, and the current sensor 10a. -10d, rotational position sensors 11a, 11b, and phase / velocity calculators 12a, 12b, two sets each. The operations of the motor torque controllers 8a and 8b, the motor current controllers 9a and 9b, and the phase / speed calculators 12a and 12b are the same as those in the first embodiment.

  Based on the steering angle command and the braking / driving force command, the vehicle controller 14 sends not only the longitudinal driving force of the vehicle but also the motor torque command values T1 * and T2 * for manipulating the yaw moment to the motor torque controllers 8a and 8b. The voltage command value Vc * is supplied to the inverter voltage controller 13.

  As shown in FIG. 7, the first and second motors 1a and 1b are respectively connected as drive motors to the right rear wheel 18a and the left rear wheel 18b of the electric vehicle (vehicle body 16). That is, the electric vehicle shown in FIG. 7 is an electric vehicle in which the first and second motors 1a and 1b independently drive the left and right rear wheels 18a and 18b. In this case, the vehicle controller 14 in FIG. 6 gives motor torque command values T1 * and T2 * having the same magnitude and different signs to the motor torque controllers 8a and 8b in order to generate the yaw moment.

  For example, when the electric vehicle operates the regenerative brake before the curve, the regenerative power blocking means 15a indicates that the regenerative power is supplied to the battery 4 when the first and second motors 1a and 1b perform regenerative braking. Stop. That is, the inverter voltage controller 13 controls the voltage Vc of the smoothing capacitor 3 to be higher than the voltage of the battery 4. When the driver steers at the entrance of the curve, a steering angle command is input to the vehicle controller 14, and the first and second motors 1a and 1b have the same magnitude but different signs in order to generate a yaw moment. Torque command values T1 * and T2 * are given.

  According to the second embodiment, the regenerative power blocking means 15a blocks the regeneration of the regenerative power of the first and second motors 1a and 1b to the battery 4, thereby smoothing the plurality of motors 1a and 1b. Since the capacitor voltage can be boosted, the entire device can be reduced in size as compared with the case where the voltage is boosted using a device such as a DCDC converter.

  Further, after boosting, when the regenerative power and power running power of the plurality of motors 1a and 1b become equal, the boosted voltage can be maintained.

  Further, the first and second motors 1a and 1b that drive the left and right wheels 18a and 18b independently are prevented by preventing the regenerative power of the first and second motors 1a and 1b from regenerating to the battery 4. The voltage Vc of the smoothing capacitor 3 can be boosted. As a result, it is possible to generate a torque sufficient to realize yaw moment control by the difference in driving force between the left and right wheels 18a and 18b, and the motion performance of the electric vehicle is dramatically improved. In other words, the currents of the first and second motors 1a and 1b are controlled in accordance with the torque command values T1 * and T2 *, respectively, and the first and second motors 1a and 1b generate substantially the same amount of power. Power running and regeneration are performed. For this reason, there is almost no charge transfer to the smoothing capacitor 3, and the voltage Vc is kept at a high value.

  As described above, after the regenerative power is used to control the voltage Vc of the smoothing capacitor 3 to be higher than the battery voltage, the power running power and regenerative power of the first motor 1a and the second motor 1b are substantially equal. Torque is controlled and high voltage can be maintained.

  For this reason, as shown in FIG. 8, the first and second motors 1a and 1b are powered by the second voltage limit line, not by the first voltage limit line limited by the voltage Vc of the battery 4b. It becomes possible to regenerate and to increase the upper limit value of the yaw moment of the electric vehicle.

  Further, when accelerating near the curve exit, the voltage Vc of the smoothing capacitor 3 can be kept high, so that the acceleration after passing the curve can be increased. As a result, a comfortable maneuverability can be provided to the driver.

  In addition, although the case where the 1st and 2nd motor 1a, 1b drives the left-right rear wheel 18a, 18b independently was shown, only one of the 1st and 2nd motor 1a, 1b gives the driving force of a vehicle. It is a traveling motor to be generated, and the other motor may be a non-traveling motor.

  Moreover, although the case where both the 1st and 2nd inverter 2a, 2b was connected to the battery 4 via the regenerative electric power prevention means 15a was shown, this invention is not limited to this. A part of the first and second inverters 2a and 2b, that is, only one is connected to the battery 4 through the regenerative power blocking means 15a, and the remaining part, that is, the other inverter is connected to the battery 4 without passing through the voltage blocking means 15a. It may be connected directly to. The motor connected without using the regenerative power blocking means 15a can be operated efficiently without being affected by unnecessary boosting of the smoothing capacitor 3.

(Third embodiment)
As shown in FIG. 9, the motor driving apparatus according to the third embodiment includes three motors (first to third motors 1a to 1c) and power to the first to third motors 1a to 1c. Three power converters (first to third inverters 2a to 2c) to be supplied respectively, and a smoothing capacitor 3a connected between the positive and negative electrodes of some inverters (first and second inverters 2a and 2b) The smoothing capacitor 3b connected between the positive and negative electrodes of some other inverters (third inverter 2c) and the DC power source (battery) connected between the positive and negative electrodes of the first to third inverters 2a to 2c 4 and regenerative power blocking means 15a connected between the battery 4 and the smoothing capacitor 3a. That is, in the third embodiment, there are three combinations of the inverters 2a to 2c and the motors 1a to 1c. The positive and negative buses of the first and second inverters 2a and 2b are connected in parallel to the smoothing capacitor 3a, and are connected in parallel to the battery 4 via the regenerative power blocking means 15a. The positive and negative buses of the third inverter 2c are connected in parallel to the smoothing capacitor 3b and the battery 4 without going through the regenerative power blocking means 15a. The regenerative power blocking means 15a includes a diode 5 and a semiconductor switch 6 connected in parallel.

  The motor driving device further includes a voltage sensor 7a for measuring the voltage value Vc of the smoothing capacitor 3a, a voltage sensor 7b for measuring the voltage of the battery 4, motor torque controllers 8a to 8c, and motor current controllers 9a to 9a. 9c, a current sensor for measuring a current flowing between the first to third motors 1a to 1c and the first to third inverters 2a to 2c, a rotational position sensor 11a to 11c, and a phase / speed calculator 12a. To 12c, an inverter voltage controller 13 and a vehicle controller 14a. That is, corresponding to the combination of the first to third inverters 2a to 2c and the first to third motors 1a to 1c, motor torque controllers 8a to 8c, motor current controllers 9a to 9c, current sensors, The rotational position sensors 11a to 11c and the phase / speed calculators 12a to 12c are in groups of three. The operations of the motor torque controllers 8a to 8c, the motor current controllers 9a to 9c, the phase / speed calculators 12a to 12c, and the inverter voltage controller 13 are the same as those in the first embodiment, and the vehicle control The operation of the device 14a is the same as that of the second embodiment.

  As shown in FIG. 10, the first and second motors 1a and 1b are connected as drive motors to the right rear wheel 18a and the left rear wheel 18b of the electric vehicle (body 16), respectively, and the third motor 1c is a front wheel. 17a and 17b are connected as drive motors. That is, the electric vehicle shown in FIG. 10 is an electric vehicle in which the first to third motors 1a to 1c independently drive the left and right rear wheels 18a and 18b and the front wheels 17a and 17b. In this case, as shown in FIG. 11A, the first and second motors 1a and 1b are regeneratively operated, and the inverter voltage controller 13 shown in FIG. 9 controls and increases the voltage Vc of the smoothing capacitor 3a. At this time, since the first and second motors 1a and 1b perform a regenerative operation, regenerative power is generated in the vehicle. The total regenerative electric power (brake torque) by the first and second motors 1a and 1b, that is, the total rear wheel torque is obtained by adding the brake torques of the motors 1a and 1b as shown in FIG. Value. As shown in FIG. 11C, the vehicle controller 14a in FIG. 9 adds a power running torque corresponding to the sum of the brake torques to the torque command value T3 * of the third motor 1c. When the steering angle command is input to the vehicle controller 14a, the first and second motors 1a and 1b have the same size and different sizes as shown in FIG. 11A in order to generate a yaw moment. Generates the same power / regenerative torque. Therefore, as shown in FIG. 11D, the first to third motors 1a to 1c generate a constant torque as a whole vehicle.

  Therefore, it is possible to boost the voltage Vc of the smoothing capacitor 3a while the front / rear force of the entire vehicle exhibits the magnitude intended by the driver and the driver does not brake before the curve or the like. It is possible to increase the voltage limit of the second motors 1a and 1b.

  According to the third embodiment, the regenerative power blocking means 15a prevents the regenerative power of the first and second motors 1a, 1b from regenerating to the battery 4, thereby driving the left and right wheels independently. The second motors 1a and 1b can boost the voltage Vc of the smoothing capacitor 3a. As a result, it becomes possible to generate a torque sufficient to realize the yaw moment control by the driving force difference between the left and right wheels, and the motion performance of the vehicle is dramatically improved.

  Further, the first and second motors 1a and 1b connected to the battery 4 through the regenerative power blocking means 15a perform regenerative braking and generate regenerative power without braking. The regenerative power blocking means 15a prevents the regenerative power from being regenerated to the battery 4, so that the voltage Vc of the smoothing capacitor 3a can be boosted. At the same time, a power running driving force corresponding to the regenerative electric power by the first and second motors 1a, 1b is generated by the third motor 1c connected to the battery 4 without passing through the regenerative blocking means 15a. The entire driving force can exhibit the value requested by the driver. As a result, the first and second motors 1a and 1b via the regenerative power blocking means 15a can use a high voltage, so that the acceleration performance can be improved.

  As described above, the present invention has been described with reference to the first and third embodiments and modifications thereof, but it should be understood that the description and drawings constituting a part of this disclosure limit the present invention. is not. From this disclosure, various alternative embodiments, examples and operational techniques will be apparent to those skilled in the art. That is, it should be understood that the present invention includes various embodiments not described herein. Therefore, the present invention is limited only by the invention specifying matters according to the scope of claims reasonable from this disclosure.

1 is a block diagram showing a motor drive device according to a first embodiment of the present invention. It is a block diagram which shows the motor current controller of FIG. It is a flowchart which shows operation | movement of the inverter voltage controller of FIG. It is a graph which shows the torque and speed characteristic of the motor in the motor drive device of FIG. It is a block diagram which shows the motor drive device which concerns on the modification of 1st Embodiment. It is a block diagram which shows the motor drive device which concerns on 2nd Embodiment. It is a schematic diagram which shows an example of the electric vehicle carrying the motor drive device of FIG. It is a graph which shows the torque and speed characteristic of the motor in the motor drive device of FIG. It is a block diagram which shows the motor drive device which concerns on 3rd Embodiment. It is a schematic diagram which shows an example of the electric vehicle carrying the motor drive device of FIG. FIG. 11A to FIG. 11D are graphs showing operation procedures of the first to third motors in the motor drive device of FIG. It is a graph which shows the torque and speed characteristic of the motor in the conventional motor drive device.

Explanation of symbols

1, 1a, 1b, 1c: Motor (traveling motor)
2, 2a, 2b, 2c: Inverter (power converter)
3, 3a, 3b: Smoothing capacitor 4: Battery (DC power supply)
5: Diode 6: Semiconductor switch 7: Voltage sensors 8, 8a, 8b, 8c: Motor torque controllers 9, 9a, 9b, 9c: Motor current controllers 10a, 10b, 10c, 10d, 10e, 10f: Current sensor 11 11a, 11b, 11c: Position sensors 12, 12a, 12b, 12c: Phase / speed calculator 13: Inverter voltage controllers 14, 14a: Vehicle controllers 15a, 15b: Regenerative power blocking means 16: Vehicle bodies 17a, 17b: Front wheels 18a, 18b: Rear wheels 100a, 100b: Subtractor 101: 3-phase / dq axis coordinate converter 102: dq axis current controller
103: Non-interference controllers 104a, 104b: Adder 105: dq axis / 3-phase coordinate converter 106: PWM generator

Claims (9)

A motor that generates regenerative power by rotational force and regenerative braking;
A power converter that supplies power converted to the rotational force to the motor;
A smoothing capacitor connected between the positive and negative electrodes of the power converter;
A DC power source connected between the positive and negative electrodes of the power converter;
Regenerative power blocking means that is connected between the DC power supply and the smoothing capacitor and prevents the regenerative power from being supplied to the DC power supply when the motor performs the regenerative braking. Motor drive device. A plurality of motors that generate regenerative power by rotational force and regenerative braking;
A plurality of power converters each supplying power converted into the rotational force to the motor;
A smoothing capacitor connected between the positive and negative electrodes of at least some of the power converters;
A DC power source connected between positive and negative electrodes of the at least some of the power converters;
Regenerative power blocking means that is connected between the DC power supply and the smoothing capacitor and prevents the regenerative power from being supplied to the DC power supply when the motor performs the regenerative braking. Motor drive device.   The motor driving apparatus according to claim 1, wherein the regeneration prevention unit includes a diode and a semiconductor switch connected in parallel.   The motor driving apparatus according to claim 1, wherein the regeneration preventing unit includes a relay. A driving motor for generating regenerative electric power by driving force and regenerative braking of the electric vehicle;
A power converter that supplies power converted to the driving force to the motor;
A smoothing capacitor connected between the positive and negative electrodes of the power converter;
A DC power source connected between the positive and negative electrodes of the power converter;
Regenerative power blocking means that is connected between the DC power supply and the smoothing capacitor and prevents the regenerative power from being supplied to the DC power supply when the traveling motor performs the regenerative braking. An electric vehicle. A plurality of motors that generate regenerative power by rotational force and regenerative braking;
A plurality of power converters each supplying power converted into the rotational force to the motor;
A smoothing capacitor connected between the positive and negative electrodes of at least some of the power converters;
A DC power source connected between positive and negative electrodes of the at least some of the power converters;
Regenerative power blocking means that is connected between the DC power supply and the smoothing capacitor and prevents the regenerative power from being supplied to the DC power supply when the motor performs the regenerative braking.
At least a part of the motors is a traveling motor that uses the rotational force as a driving force of the electric vehicle.   The travel motor includes the travel motor connected to the DC power source through the regenerative power blocking unit, and the travel motor connected directly to the DC power source without passing through the regenerative power blocking unit. The electric vehicle according to claim 6, comprising:   The travel motor includes a travel motor that independently drives a left wheel and a right wheel of the electric vehicle, and the travel motor is connected to the DC power source via the regenerative power blocking means. The electric vehicle according to claim 6.   The regenerative power is generated in a traveling motor connected to the DC power supply via the regenerative power blocking means, and the regenerative power is directly connected to the traveling motor connected to the DC power supply without passing through the regenerative power blocking means. The electric vehicle according to claim 6, further comprising a vehicle controller that generates a driving force by adding a power running driving force equal to the magnitude of electric power.

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